DESCRIPTION High fat diets are widespread in the United States and are a contributing factor in the development of cardiovascular disease, diabetes, obesity, and high cholesterol. Widespread availability, inexpensive cost, and pervasive marketing of high fat foods are environmental factors that influence the population prevalence of high-fat diets. Because virtually the entire population is exposed to these influences, intervention strategies that modify the environment may make an important contribution, alone or in combination with more traditional educational approaches, to the goal of improving population food selections. The proposed study examines the role of pricing and nutrition education on purchases of low fat food snacks through vending machines. Four pricing levels of low fat versus regular snack price (same price, low fat reduced 10%, low fat reduced 25%, and low fat reduced 50%) will be crossed with three education levels (no education, low fat labeling, and low fat labeling plus active promotion). The twelve experimental conditions will be in a Latin square design. Twenty-four vending machine sites will implement each of the twelve conditions over a two-year period. The effectiveness of the interventions will be tested in both adult and adolescent populations by using twelve vending machines in worksites and twelve in high schools. Sales of low fat and regular snack items will be measured. Results are intended to provide information on environmental interventions that are easily implemented at a relatively low cost to promote choice of lower fat foods in the general population. The economic impact of this approach will provide information on the extent to which these strategies will appeal to vendors and vending sites in real-world settings.